8GB RAM install, Computer Powers up but little else, Is it Faulty RAM?

I bought 8GB (2x4GB) for my Win7 64bit PC. After installing it (I’m positive it was installed correctly) I turned the power on, the light on my PC came on (no beeps from the PC), however no output was being sent to the monitor. I left it awhile to see if I heard the sounds of windows booting from the speakers, but they never came.

I have since tested the RAM with 1 old stick and 1 new stick however the same happens.
However if I place both old sticks back in, the computer boots up fine.

To me, it would seem like its faulty RAM, as I checked the comparability before buying but if there is any other explanation that is fixable without returning the RAM, I would prefer that option.

Does anyone have a solution to this problem?